Compound steam-engine



(N0 Model.)

J. F. KRIEGER & J. H. EIOKERSHOFF.

GOMPUND STEAM ENGINE.

Patented May 19, 1885.

W/T/VESS. INVE/VTORS UNITED STATES PATENT OFFICE JOHN F; KRIEGER AND JOHN H. EIOKERSHOFF, OF CINCINNATI, OHIO.

compo'uuo STEAM-ENGINE.

SPE-CIPICA'I'ION forming part of Letters Patent, No.-318,003, dated Ma.y 19, 1885. Applicalioh filcd February 20, 1885. (N0 model T0 all w7wm it may concern:

Be it known thal: we, J OHN F. KRIEGER and J OHN H. EIOKERSHOFF, citizens of ohe United Staates, residing ab Cincinnati, Ohio, have invented -new and useful Improvements in Gompound Steam-Engines, cf which the following is a specifioabion.

Our invention relates to that; dass of double 01 compound engines in which the smaller 01 high-pressure cylirider acts as a valve-chest and its piston as a governing-valve fo1 the larger or expansion cylinder and piston, its 0bjeob being to improve their construction and the efiioiency and economy of their operabion.

As heretofore constructed, the form cf engine to which our improvements are applied not only exhausted.from the expansion-cylinder between the piston-heads constituting the double piston of the primary 01 highpressure cylinder, buta also exhausted the residual live steam from the primary-cylinder through an ordinary and separate exhaust-oavity and governed poru of a D-vaNe and seat. Ab eaeh stroke, therefore, of the primary piston there was a loss of the residual live steam employed in driving said piston. Moreover, a cut-o'ff valve was applied by means of a supplemental valve-chest in order 130 enable tl1e engine to be worked expansively as a true compound-engine; but such waspraetically dei'eated by reason, annong others, of the loss of steampressure in the large opening afforded by the intermediate steam-chesb. These (lefects involved a serious loss of economy and effieieucy in the operation of such engines, which it is the objecb of our inveution to remedy.

T0 this end our invention consists in a coustruction dispensing entirely with t-he D-exhaust valve and its exhaust-port, substituting therefor an admission-valve by which the high-pressure exhaust is entirely avoided, and the resdual live steam, afte1 supplying the expansioucylinder, instead of being exhausted independently fron1 the high-pressure cylinder is retained therein as a eushion for the high-pressure piston and afterward utilized in the expansion-cylinder; and ib cousists, further, in the combination, wibh such admission-valve, a cut-off valve applied within t-he valve-chesb directly to said admissionvalve, thereby nob only dispensing with the extra valve ohest and ports and avoiding'the loss of power incident to filling the valvechest; with steam of high initial pressure after each closure of the cut-ofi valve, bub also perfectly regulating the relative expansion an'd disbribubion cf steam in both cylinders.

Mechanism embodying our invention is illustrated in the accompanying drawings, forming part of tshis specification, which rep resents longitudinal sections of both cylinders in a common axial plane, showing their pistons, connecting steam-passages, and the valves and admission-ports.

In these drawings, A designates tl1e secondary or expansion cylinder; a, its piston; B, the primary or high-pressure cylinder; b b, its double piston; c c, the connecting steanr passages between the cylinders; (J, the valvechest located upon the primary cylinder, and d d the steam-admission ports opeuing from the valve-chest O into the cylinder B.

The governing-valve D for tl1e ports d d is of rectangular form, without exhausbcavity .having parallel faces above and below, and

provided Wihh vertica-l apertures e e, corresponding with the porb-openings, but separated loy a greater interval, extending through both faces of the valve near it-s exbremities.

Upon the upper face of the valve D is fitted a two-parb cut-off valve, E, adjustable in length upon a stem, s, engaging its parts loy right and left screwthreads, respectively, said stem projecting rearward through the valve-chest O, and being therc provided with a manipulatinghand-wheel, g,engaging asuitable spline or groove upon the stem.

The parts thus described are provided with the ordinary connections and oj erating mechanism,which we have not deemed it necessary 110 exhibit or describe, as they are nob mate= rially concerned in our improvements excepb as stated.

Ihe operation is as follows: In the travel of 5 the primary or high-pressure piston itz uncovers the ports c, through which the sbeam, haveach of the other. When the piston b on its rturn-stroke again passes a 110171; c, t-he induction-valve D being closed the partially-spent steam is not allowed t0 escape, but is cushioned behind the piston b and eonnpressed ultimate- ]y to near its initial pressnre, and again ntilized in connection with the new snpply of live steam upon opening the admission-port d for a repetition of the stroke. T he exhaust ultimately takes place solely fron1 the (expansioncy1inder between the heads b 0f the primary piston by a portf, opening ab mid-lengbh of the prirnary cy1indet.

II; Will readilybe pereeived thab by suitably proportioning the admission va1ve and ports and by proper adjustrnent 0f the cut-off valve Ehe live steam is not only economized with reference to the ordinary loss oceurring in the admission-ports, bat; its effective power may be most; economicallyrealized by permitting a parbial expansion in the primary cylinder, t0 be afterward completed.in the secondary cylinder, whi1e no stean1 i s exhausted fron1 be engine unbil it has Clone its work in both cylinders; also, that by Ehe direct applieation of the cut-off va1ve t;o the admission-valve all 1oss ofsteam oceurring through a suppl ernental chest is avoided.

An incidental advantage ofthis construetion is that by proper adjustment 0f the cut-off va1ve the engine may be started by admitning live steam 130 boh eylinders, and afterward, as it gathers force and momenturn, the valve n1ay be readjusbed t0 operate the engine as a true compound engine.

lt will be obvions that some of the advantagesherein enumerated may be attained with out using any cut-off valve, the admissionva1ve D being given sufficient 1ap 150 secure the desired eompression, and such modification we conceive t0 be within the spirin of our invention.

We claim as our invention and desire t0 secure by Letters Patent 0f the United States l. In a. colnpound engine, ehe combination 0f high and 10W pressurecylinders, the former carrying a donble piston operating as a con tro1ling induebion and eduebion va1ve f01 the latter, an exhausbport opening frorn the highpressure eylinder between the pistons thereof, and an inductiomvalve arranged to govern the adxnission 0f steam to the high-pressure eylinder, whereby Lhe stean1 is solely exhausted fron1 the engine, firsl: from the high-pressure into the low-pressure oylinder, and then back and ounward throngh the sole exhausb-porb between the pistons of the high-pressure cy1inder, as seb forth.

2. In a eomponnd engine 0f the dass described, the eombination 0f the high-pressnre and low-pressure cylinders am]. their pistons and connecting-ports, having its s0le exhzmst; fro1n the high-pressnre cylinder into the 10W- pressure cylinder, and fron1 thence oubward bebween the highpressure pisbons, With an inductzion-valve governing the high-pressure cylinder, arranged 110 retsain rhe residual 01 unexhausbed steam in the high-pressure cylinder as a cushion for its pisbon, subsbantially as Set; forth.

3. In a componnd engine 0f the dass described, having its sole exhaust; from the high inbo the 10W pressnre cylinderand fr0m thence outward through the high-pressure piston, an

adjustable cut-off valve, arranged 218 described in combinataion with thein@nctionvalve high and 10W pressure cylinders, connecting-port-s, und single exhausb-portf, substantially a.s and for the purpose seb forth.

In testirnony whereof we have hereunto S t 0111 hands in the presence 0f two subscribing witnesses.

JOHN F. KRIEGER. JOHN H. EICKERSI-IOFF.

\Vitnessesz L. M. HOSEA, R. D. GALLAGHER. 

